I want to know, can we use GeoExt freely? is there any need to purchase some license for using GeoExt ?

Actually i am already working with free Open source tools (OpenLayers+GeoServer) for my webMap applications. But i need some specific functionality which is possible with GeoExt. so can i use GeoExt freely with Openlayers and GeoServer ?

Ext is free for commercial use, so long as you can adhere to the terms of the GPL. If you can not (Or don't want to figure out if you can), you can purchase commercial licenses.
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Christopher SchmidtJan 26 '12 at 15:27

It's a little more complicated than that. For example, you should be able to use it on a company internal web-site without issue. But, it's best to avoid GPL Javascript libraries for public web-site if only for the headache in figuring out what is permissible.
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SeanApr 11 '11 at 19:00

We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.

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iant♦Aug 14 '12 at 10:34